Moulded rubber footwear



Nov. 20, 1962 .1. TUsA ETAL MOULDED RUBBER FOOTWEAR Filed Dec. 23. 1960Inventor@ Jaim 736g. d

Attorney United States 3,064,288 MULDED RUBBER FQDTWEAR John Tusa,Horndon-on-the-Hill, and George Hollington, Chadweil-St. Mary, England,assignors to Bata Shoe Company lnc., Belcamp, Md.

Fiied Dec. 23, 196), Ser. No. 77,906 Claims priority, application GreatBritain Nov. 17, 1953 4 Claims. (Cl. 12-142) This invention relates tofootwear (hereinafter and in the claims referred to generally as shoes)formed partly of rubber or the like (hereinafter and in the claimsreferred to simply as rubber) with insoles. This application is acontinuation in part of applicants prior copending application SerialNo. 468,913, led November l5, 1954, now abandoned. The inventionembraces inter alia kneeboots of the Wellington type, and sports shoesincluding sports shoes having textile uppers.

It is known to incorporate in shoes, such as aforesaid, insoles whichare cut in a clicking press from a sheet of vulcanised sponge rubber.The waste material cannot be re-used except after a process of re-claimtreatment.

According to the present invention we provide a method of making shoesformed wholly or partly of rubber, with an insole comprising bondingtogether a layer of textile material and a composition of vulcanisablerubber containing a sponging agent, building-in an insole of said bondedmaterial with a vulcanisable rubber sole, saidv composition beingbetween the textile material and the sole, and vulcanising the sole andinsole in situ, whereby the sole and insole become integrally united andthe insole becomes sponge rubber under control of the textile material,through which the sponging gases escape.

An embodiment of the invention will now be described merely by way ofexample, with reference to the accompanying drawings, in which:

FIG. l is a transverse section through the foot part of a kneeboot ofthe Wellington type built-up on a hollow last and constructed inaccordance with the present invention.

FIG. 2 is a fragmentary transverse section through the leg part of sucha kneeboot.

In the drawings, for simplicity of description, the hoot and last areshown with the ground-engaging surface of the sole lowermost, as whenthe boot is worn on the human foot; but in actual manufacture, as iscustomary, the last would be positioned to hold the boot upside down.Moreover, for clearness of illustration, the thickness of the severalthin components are drawn exaggerated.

Referring firstly to FIG. l, the sole of a kneeboot of the Wellingtontype formed on a hollow aluminium last 1 comprises a main or outer sole2 of vulcanisable rubber, a main or lower intersole consisting of layers3 of vulcanisable rubber and an intermediate layer 4 of textile fabric,and an upper insole consisting of an under layer 5 of a composition ofvulcanisable rubber containing a sponging agent bonded on its uppersurface to a top layer 6 of porous textile fabric. 'Ihe upper of thekneeboot, at the foot part thereof, consists of a porous textile fabriclayer 7 bonded to an outer vulcanisable rubber layer 8 and the lowerends of these layers 7 and 8 are turned in under the layer 5. Avulcanisable rubber foxing 9 secures the rubber layer S to the main sole2.

The leg part of the upper of the kneeboot, as shown in FIG. 2, may haveinterposed between the fabric and rubber layers 7 and '8, respectively,a layer 10 composed of vulcanisable rubber containing a sponging agent.

In assembling the various components of the boot, namely the sole 2, theintersole 3, 4, 3, the insole 5, 6, the upper 7, 8 and the foxing 9,their inter-engaging surgyjzgg Patented Nov. 20, 1952 faces are coatedwith vulcanisable cement, as is customary in the manufacture of built-upshoes consisting or including rubber components to be vulcanised andthereby permanently bonded together.

When the boot components are assembled, as shown, on the hollowaluminium last 1, the whole is introduced into the vulcanising boilerand is subjected therein to vulcanising and sponging heat and pressure,involving the three following pressures:

(l) The customary gas pressure in the boiler acting on the exterior ofthe boot.

(2) Pressure by the hollow aluminium last reacting on the interior ofthe boot.

3) Pressure on the welds between sole, insoles, foxing and upper causedby expansion of the sponge rubber of the insole caused by the productionof gases during vulcanisation and sponging.

The porosity of the fabric layers 6 and 7 allows for controlled escapeof gases from the sponge rubber layers 5 and 10 during vulcanisation andsponging. The escaping gases, after penetration of the fabric layers 6,7 pass away between the layers 6, 7 on the one hand and the smoothsurface of the last 1 on the other hand.

After vulcanisation and sponging, the rubber components of the bootconstitute an integral whole, the rubber components all uniting intoeach other under the heat and pressure within the boiler.

The layers 5 and 10 may initially be bonded with the fabric layers 6 and7, respectively, directly by means of a three bowl calendar.

The sponge rubber insole may be made of any desired thickness.

As a result of the invention:

(a) The insole of a built-up shoe is produced in vulcanised spongerubber form and is incorporated as an integral component of the shoe byone operation.

(b) Clicking press waste in the initial work of stamping insoles from asheet of unvulcanised sponge rubber material can be re-used withoutreclaiming as is the case with pre-vulcanised waste material.

(c) During vulcanisation internal pressure is exerted by expansion ofthe sponging rubber of the insole against the other parts of thebuilt-up shoe in opposition to the pressure in the boiler, so that thesponge rubber of the insole is spread outwards and completely seals thebottom of the shoe and will lill-in any small spaces round the insole 5,6 and the intersole 3, 4 underneath it.

In the example, the insole consists of a sponge rubber under layer 5with a textile top layer 6 bonded to it, having been stamped frommaterial consisting of a sheet of textile fabric coated with a layer ofuncured sponge rubber composition. If desired, the initial layer 5 ofvulcanisable rubber and sponging agent may be interleaved between topand bottom textile layers, all finally bonded together by thevulcanising procedure. Lighter fabrics may replace the heavier and moreexpensive ones for the bootee type of shoe, such lighter fabrics givingWarth and heat retention equivalent to heavier fabrics. The compound maybe applied byspraying or spreading or by coating by a Ventilatingcoating method.

We claim:

l. A method of making shoes comprising building together on a last thefollowing components, namely, a sole incorporating vulcanisable rubber,an upper and an insole incorporating a top layer of porous fabric and,in direct contact therewith, a-n under layer composed of a compositionof uncured vulcanisable rubber containing a sponging agent, andsubjecting said components on the last to heat and pressure by anexterior fluid pressure medium to vulcanise the rubber constituents andto convert said composition into vulcanised sponge rubber, the procedurebeing such that compressed gases produced in fabric and the last andsaid components are under the exterior pressure` of sa-id'medium--thereactive interior pressure of the last andthe internal pressure of saidgases, soy that the components are united as an integral whole.

2. A method of making shoes according to claim 1 in which the insole isof material made beforehand by coating a sheet VofV textile fabric Ywitha layer of uncured sponge rubber composition and stamping the insolefrom the coated sheet.

3. A method of making shoes according to claim 1 in which the' insole ismade by coating a-n uncured sponge rubber composition on to uncoatedtextile material con,- stituting the top layer of porous fabric.

4 4. A method of making shoes according to claim 1 and includingbuilding-in a lining of porous fabric, to which is bonded an uncuredAsponge rubber composition with the shoe upper before vulcanising.

References Cited inthe le of this patent UNITED STATES "PATENTs 823,928VClark ..i June 19, 1906 989,089- Warner Apr. 11, 1911 1,309,047 PriceJuly- 8, 1919 1,924,716 Ferrettie Aug. 29, 1933 2,287,026 Craig et al.June 23, 1942 2,586,045 Hoza Feb. 19, 1952

